We love the Caymans and Turtle Nest Inn and there are many fine dive ops on the island. We've had good experiences with Cayman University Divers but TNI has a relationship with DNS dive op and they are another fine company.
You didn't say how many people will be in your party and how many are divers? Are you looking for a 1-bedroom apartment/condo or something larger? You can find both at TNI and there is very nice snorkeling right off the beach and the rental car is included.
But as much as I love TNI, if I was planning to do that much diving on GC, I might prefer to stay at a place with an onsite dive op just for the convenience and because it would be closer to the marina and rush hour traffic can be difficult. Or I might look for a place without an onsite dive op but on the West Side but North of Seven Mile Beach, closer to most of the shore dives and an easier drive to the West Bay Marina to meet many of the dive boats.
When we go to GC we mostly snorkel and shore dive and if the weather is good we will arrange a few boat dives. We tend to spend our first week relaxing on GC and TNI is perfect for that, and we spend our second week on Brac or Little at a dedicated-dive resort, although one time we boarded the Cayman Aggressor and did a lot of diving.
A few places on GC with onsite dive ops include:
- Compass Point - is on the East End and far from many restaurants, shops, and activities but close to East End diving and the onsite dive op (Ocean Friends) offers valet services. No onsite shore dive. Small beach on the property. (Morritt's is a large condo complex nearby and Red Sail is the onsite dive op.)
- Sunset House - South of George Town and the Seven Mile Beach. Breakfast is included but they do not offer apartments or kitchenettes so you will be eating out much of the time and that can get expensive on GC. There is no beach but there is an onsite shore dive, although it has gotten mixed reviews. If you are a photographer, you will appreciate Cathy Church's onsite photo store and gallery. Sunset Divers is the onsite op and it is all ironshore, no beach.
- Lighthouse Point condos offer a great onsite shore dive and DiveTech is the onsite dive op. They are also the dive op at the Holiday Inn on the North End and will transport you to the shore dive or the marina if you stay at HI. I believe that most of the LP condos are larger but they are advertising a "couples special" with 1-bedroom units, but I don't know if these have full kitchen facilities. It gets very expensive to eat out 3 times a day on GC so a kitchen is a good option. There is no beach at LP.
- Coconut Bay Condo's are near Lighthouse Point and sit on a couple of great shore dives called Hepp's and Stingray Divers is the onsite op. But they only offer large, 3-bedroom condos so that may be too big for your party. There might be a small beach, I am not sure.
- Cobalt Coast is further North and they offer an all-inclusive option as well as some units with kitchen facilities. They are situated close to the beautiful North Wall and offer unlimited shore dives on the house reef, but the shore dive can get winded out pretty easily. Reef Divers is the onsite dive op and they provide valet services. They have a small, man-made beach.
Our favorite shore dive, Turtle Reef at Macabuca, is near Coconut Bay and Light House Point and the onsite dive op is Sun Divers and it costs about $15 CI to rent a tank and weights.
Grand Cayman isn't like Bonaire. You don't load up your car or truck with tanks and drive from shore dive to shore dive. Most shore dives have onsite dive ops and you rent tanks and weights from them. Resorts with onsite dive ops and shore dives usually offer unlimited shore dives on the house reef on days when you are boat diving with them - or you can rent shore dive tanks and weights from them if you are just passing through.
We rarely bother with the most famous shore dives of Eden Rock and Devil's Grotto, because there can be overrun with cruise ship divers and snorkelers and these sites have suffered a lot of damage. But there is always good fish life on these dives and they are easy. Since you are going in the spring/summer - find out if the Silversides are visiting, because that can really be something to see! Eden Rock Dive Center is the onsite dive op.
Having said all of the above, we still love Turtle Nest Inn, it is centrally located with access to the entire island. It is clean and comfortable but not luxurious. There are some restaurants nearby, but most of the popular restaurants are on the 7MB. The TNI managers and staff are friendly and pleasant. There is a nice little beach right outside but it is not the endless powdery white sands of 7MB, but the snorkeling is good.
The snorkeling reef is close and shallow and you have to get past some rocks and turtle grass to get there, but it isn't bad at all - not ironshore. But if you stay at TNI you have to be willing to do some driving on the left side of the road and deal with traffic if you are trying to get to the West Bay Marina or shore dive sites during rush hour. It might be easier to head to the East End to dive with Ocean Friends at Compass Point or Red Sail at Morritt's Resort.
But TNI is a real bargain IMO and it helps a lot to have the rental car included in the price. There are a lot of great places to stay and dive on GC, let us know what you decide to do!